Needle throat for buttonhole-sewing machines



Jan. v26, 1926.

1,570,661 A. R. wooD NEEDLE THROAT FOR BUTTONHOLE SEVNG MACHINES Filed Dec. 28, 1923 2 Sheets-Sheet 1 .Jm. ze, 1926. 1,570,661

A. R. WOOD NEEDLE '11111011' Fon U'rTon'xoL SWING 111011111115 Filed Deb. 28, 192:5 l 2 sheets-shan 2 INVENTOR ATTORNEY Patented Jan. 26, 1926.

UNITED STATES @FFI-CE..

AL, 1. Wieon, or 'fisrffd "io "i'NU- FACTURING COMPANY, OF ELIZABETH, NEW JKSEY; A CGRPOB'ATION dr NEW mmm wnnxm Foie UTToHL-ewnw inciting.

Appicandn fue@ Deemi 28, 1923: 'Seal .15m lssagosz.

'te @"pee en aree-.df fabriefif the action e' ledxhe butmnholi slit' cutter.

which th huttonhel'e is Stitched are neces sa'rily' firmly incorporated' or bo-nd together arlmd. the 'huttonhele-sli-f by the previously,

-ffeulty has' hertofre' been experienced in sewing acep'rtable' lduttnholes' in certain essees fofgmaitriatuch 'ais spongy fabric or leather. The buttonhol's. refusa-ally 'ewn distdrted `by `yhe needle-thmxt member; whereby the cuit''edge of :the bttqnhole slit `s pushed to' one-side. and out `of the range of fthe' Stitch-farming .mehajnism so ,'tht vsuch *mit edge fis no't 'caughn 'and covered by the 'overs'e'am This tali-lute usually ccurs in sewing around the eye' hdalong 'the re- Itfha's been idiscve'redmhat the c'qn'vex 'leading edge ofv the needle-throt; membernew me" @hemmen ,but 'eh-isf begane its jpeadjreveiie', herebydenyieg che ihrewifngeue ff the mele-16013' end musing the manine to' fstith It has beef discveredff 'the diie'lty -fffiy be gense-muy ova-'cerne by providing a needle-throat member, the raised worksupporting portion of which, instead of being substantially circular and having a con.- vex leading edge, as heretofore, is made pear-shaped so as to present a reentrant leading edge terminating in a leading point, which edge and point operate to scoo or deflect the under ply of the work towar the buttonhole-slit, whereby the cut edges will be caught in the overseam and properly covered. The work-supporting surface of the needle-throat member is also preferably formed with a shallow groove leading upwardly and rearwardly or toward the needle-hole from the reentrant leading edge to avoid an abrupt or harsh initial engagement of such edge with the under surface of the work.

In the accompanying drawings, Fig. 1 is atransverse sectional view through the work-clamp of a buttonhole sewing machine showing the needle-throat member in front elevation when sewing down the return side of a buttonhole. Figs. 2 and 3 are respectively left and right side elevations of the needle-throat member shown in Fig. 1. Fig. 4 is a top plan view of the needle-throat member. Fig. 5 is an enlarged section on t-he line Fig. 4. Fig. l6 is an enlarged section on the line 6 6, Fig. 4, with elements of the work-clamp and the stitchforming mechanism added. Fig. 7 is a view similar to Fig. 5 with elements of the workclamp added. Fig. 8 is a perspective view of the needle-throat member from above. Fig. 9 is a perspective view of the needlethroat member and associated under thread mechanism from below. Fig. 10 is a diagrammatic view illustrating the action of a needle-throat member of the prior art and Fig. 11 is a similar view illustrating the action of a needle-throat member embodying the present invention.

In the embodiment of the invention illustrated, 1, 1 represent the lower work-supporting plates and 2, 2 the upper clamping feet of a buttonhole sewing machine having stitch-forming mechanism such, for example as that disclosed in the Allen & Faulkner Patent No. 1,372,473 of March 22, 1921, and including the reciprocating and laterally jogging needle 3 with which cooperates the under thread mechanism including the loopers 4, 5 carried by the usual rotary turret mounted in the curb or casing 6. Mounted upon the turret, as usual, is the needlethroat member in the form of a post 7, the overhanging upper portion 8 of which is formed with a button-like raised portion 9 which, in the present instance, is pear-shaped and has a reentrant leading edge-portion 10 terminating at the leading point 11 which is preferably disposed outside of the zone a, Fig. 11, of the overseam. Back of the point l1 and reentrant leading edge 10 is a shallow groove or depression 12 sloping upwardly toward the needle-hole 13 and bordered at its outer side by the ridge 12 which is curved outwardly and forwardly from the needle-hole 13 and terminates at the leading point 11 which is thus disposed at one side and in advance of the needlehole 13. The needle-throat member is provided with the usual cord-hole 14.

It will be understood by referring to Fig. 10 that the convex leading edge e of a needle-throat member of the prior art, travelling relative to the work in the direction of the arrow, will drag upon and push or deflect the under ply of material away from the buttonhole-slit, thereby stretching and distorting the material adjacent such slit. By forming the needle-throat member with a leading reentrant portion, substantially as described, the material within the zone of action of the needle-throat member, Fig. 11, will be plowed or deiiected toward the buttonhole-slit and will therefore be securely caught in the overseam and properly covered. When a buttonhole-slit is cut in spongy material the cut edges tend to `expand as shown at 15, Figs. 6 and 7 and the upwardly sloping shallow groove 12 gradually lifts the expanded cut edges into sewing position as the reentrant leading edge 10 and ridge 12 bordering the outer side of such groove plow or deflect inwardly the under ply of material.

I-Iaving thus set forth the nature of the 100 invention, what I claim herein is 1. A needle-throat member for cut-first buttonhole sewing machines, said member having a needle-clearance aperture and means for deflecting the body-material towards the buttonhole-slit.

2. A needle-throat member fo-r cut-rst buttonhole sewing machines, said member having a needle-clearance aperture and having a body-material deflecting surface inclined outwardly and' forwardly away from the needle-aperture so as to cause deflection of the body-material toward the buttonholeslit.

A buttonhole sewing machine needlethroat-I member having a needle-clearance aperture and a reentrant leading edge terminating atene side and in advance of the needle-clearance aperture in a leading point.

4. A. buttonhole sewing machine needle-- throat member having a needle-clearance' aperture and a reentrantleading edge terminating in a leading point, said member being formed in rear of said edge with a shallow upwardly sloping groove.

5. A buttonhole sewing machine needlethroat member having a needle-clearance aperture and a reentrant leading edge terminating in a leading point, said member being forme-d in rear of said edge with a shallow upwardly sloping groove bordered at its outer side by a ridge in rear of'said point. i

6. A buttonhole sewing machine needlethroat member comprising a post formed at its upper end with a button-like elevation having a reentrant leading surface-porti0n adapted to deflect the body-material toward the buttonhole-slit.

7. A buttonhole sewing machine needle-l throat member formed With a button-like 15 raised portion having a needle aperture and a leading point at one side and in advance of the needle aperture.

In testimony whereof, I have signed my name to this specification.

ALFRED R. WOD. 

